This invention relates to an antibacterial combination of an antioxidant and an extract of Magnolia officinalis, and more particularly, to an oral composition containing such combination which exhibits increased oral care effects against Streptococcus mutans, a bacterium associated with dental caries.
Compounds such as chlorhexidine, benzothonium chloride and cetyl pyridinium chloride have been used in the art as antibacterial agents in oral compositions. However, such agents experience reduced effectiveness when in presence of an anionic surfactant required for the effective performance of oral compositions such as toothpaste and mouthrinses. In contrast, noncationic antibacterial materials are compatible with anionic surfactants in oral compositions and noncationic halogenated hydroxydiphenyl ethers such as Triclosan have been effectively employed in commercial oral compositions. Notwithstanding the efficacy of such antibacterial compounds, many of these compounds are regulated by both the U.S. Food and Drug Administration and by the European Union making their applications into food and confections for oral care usage quite limited. Further, aside from their product deployment challenges relating to interactions with other ingredients and efficacy, these compounds often impart other unpleasant characteristics, including but not limiting to poor taste, potential tooth discoloration and mouth irritation to sensitive oral tissues.
Recently, interest has been generated in the medicinal properties of herbal preparations for use in oral compositions. Herbal preparations are considered “more natural” and are therefore viewed as more acceptable antibacterial ingredients to the consumer.
Extracts of Magnolia Cortex (barks of Magnolia officinalis) are known to have antibacterial efficacy. For example, it has been reported in “Dental caries Prevention by Traditional Chinese Medicines”, T. Namba et al, J. Medicinal Plant Res., vol. 44, pp. 100-106 (1982) that some active principles of these extracts, identified to be magnolol and honokiol, were bactericidal against S. mutans in the in vitro test Minimal Inhibitory Concentration (MIC). Unfortunately at high concentrations, magnolia has the potential to discolor teeth, and impart unfavorable taste characteristics; thus, providing low and efficacious levels would be more appealing and beneficial to consumers.
The dental art is continuously seeking enhanced efficacy of antibacterial compounds. An advantage of such enhancement is that the effectiveness increases, and lower quantities of the antibacterial agent are required to achieve the desired therapeutic effect while providing great taste, lower cost, and meet regulatory guidelines. Such combinations also are particularly important in the treatment of delicate or sensitive tissues, such as the oral mucosa reducing the likelihood of ulceration of oral mucous membranes, induction of desquamative gingivitis, and discoloration.
Thus, there is a recognized need for, and it would be highly advantageous, to have an antibacterial oral composition in which a combination of an antioxidant and an extract of Magnolia cortex exhibited enhanced antibacterial activity against Streptococcus mutans (S. mutans) and thereby for enhanced effectiveness against dental caries.